The ER5025S-391 from Gowanda Electronics is a RF Inductor with Inductance 3.9 uH, DC Resistance 0.4 Ohms, DC Current 0.56 A, Self Resonant Frequency 64 MHz, Operating Temperature -55 to 105 Degree C. Tags: Wire Wound Inductor. More details for ER5025S-391 can be seen below.